1. Field of the Invention
The present invention generally relates to wireless communication technology, and more particularly to an antenna structure for a mobile phone.
2. The Related Art
During product development processes of conventional communication devices, such as mobile phones, plastic shells are mainly used by manufacturers due to cost concerns, in order to maintain basic radiation characteristics of an antenna structure. But currently, a trend of metal shell is brought by Apple iPhones. Since the metal shell has light weight, good heat dissipation, high strength, high impact resistance, good looking and recyclable characteristics, the metal shell becomes more and more popular.
However, the metal shell usually generates shield which reduces efficiency of the antenna structure. For solving the problem, the metal shell is often opened with slits in positions corresponding to the antenna structure. But the slits may obviously ruin appearance of the metal shell.
Therefore, it is important to design a proper antenna structure capable of achieving a metal shell formed into a continuous metallic loop configuration for a mobile phone.